A polymer-based material such as silicone rubber and polyurethane has properties such as a bioinert property, long-term stability, strength, and flexibility, and is widely used as a medical material such as a percutaneous catheter for example. However, since the exemplified polymer-based material is bioinert, its percutaneous portion may not adhere to an anatomy, so that this embraces a possibility that: skin down-growth (phenomenon in which an epithelial tissue is internally convoluted along a surface of a catheter) may occur, and there may be a risk of bacterial infection in the convoluted tissue.
Titanium oxide is mixed and combined with a coating material, synthesis resin, ink, paper, chemical fiber, and the like, by making use of its property as white pigment. Further, titanium oxide is used, as a photocatalyst, in a deodorant, an antifoulant, an anti-bacterial/antiviral/antifungal material, an anticlouding agent, a water-treatment agent, an anticancer agent (material), and the like. Further, the titanium oxide is known as a substance, having a chemically great stability, which is free from any toxicity. Specifically, for example, it was reported that: no toxic symptoms was observed in (i) an animal experiment (L. Herget, Chem. Ztg., 82,793 (1929)) in which animal feeding stuffs containing titanium oxide was given for 16 months and (ii) an animal experiment (L. Vernettiblinate, Riforma. Med. Naples, 44,15,16 (1928)) in which hypodermic injection of titanium oxide was performed and powder of titanium oxide was inhaled. Moreover, it was reported that: no carcinogen was observed even when oral administration of titanium oxide was performed (D. S. Fredrickson, Federal Register, 43,225,54299 (1978)).
As a medical material using the titanium oxide, there are proposed (i) a dental resin composite filler having a high covering power (K. Yoshida, et al., J. Biomed. Mater. Res. Appl. Biomater., 58,525 (2001)), (ii) an anticancer agent based on a photocatalysis (R. Cai, et al., Cancer Res., 52,2346 (1992)), and (iii) a catheter which does not adhere to liquid containing substance.
Further, there is proposed a titanium oxide complex, obtained by combining the titanium oxide with the aforementioned polymer-based material, which is favorable in medical use.
A specific example of the production method of the titanium oxide complex includes “blending” based on infiltration or melting. Further, examples of a method for coating a surface of the polymer-based material with titanium oxide include a dip method, a spin coat method, a spray method, a screen printing method, and the like.
However, in the titanium oxide complex produced by the foregoing production methods, essential properties of the polymer-based material and the titanium oxide are varied. Alternatively, there is a problem that the titanium oxide exfoliates from the polymer-based material.
Specifically, in case of the titanium oxide complex produced in accordance with infiltration or melting, the essential property of the titanium oxide or the polymer-based material is lost or varied in the production process.
Further, in the titanium oxide complex produced in accordance with the method of coating the surface of the polymer-based material with the titanium oxide, the merely application of the titanium oxide to the surface of the polymer-based material is performed, that is, the titanium oxide is made to physically adhere or stick to the surface of the polymer-based material. Thus, the titanium oxide is liable to exfoliate from the surface of the polymer-based material. When the titanium oxide is liable to exfoliate from the surface of the polymer-based material in this manner, it is impossible to exhibit a function as the titanium oxide complex.
Therefore, it is required to provide (i) a titanium oxide complex in which titanium oxide firmly bond to a surface of a polymer-based material in a simple manner without deteriorating essential properties of the titanium oxide and the polymer-based material and (ii) a production method of the titanium oxide complex.